Work table with selective rotating tools



D. l. WEBB March 19, 1957 WORK TABLE WITH SELECTIVE ROTATING TOOLS Filed March 9, 1955 2 Sheets-Sheet 1 March 19, 1957 D. l. WEBB 2,785,711

WORK TABLE WITH SELECTIVE ROTATING TOOLS Filed March 9, 1955 2 Sheets-Sheet 2 United States Patent WORK TABLE WITH SELECTIVE ROTATING TOOLS Daniel I. Webb, Arlington, Mass.

Application March 9, 1955, Serial No. 493,252

1 Claim. (Cl. 144-1) This invention relates to a machine tool of a relatively simple sort comprising a worktable under which are two rotating tools selectively movable to and from an operative position. An object of the invention is to supply a relatively inexpensive apparatus for the home or small shop, including two power-driven tools such, for example, as a circular saw and rotary planer. According to the invention, these tools can be selectively moved into an operative position relative to the table, one of the tools being disposed beneath the table in an inoperative position when the other tool is projecting operatively through the table top.

For a more complete understanding of the invention, reference may be had to the following description thereof and to the drawings, of which- Figure l is a plan view of a worktable with mechanism embodying the invention;

Figure 2 is a section, on a larger scale, on the line 22 of Figure 1;

Figure 3 is a fragmentary sectional view similar to Figure 2, but With parts shown in a different position;

Figure 4 is a section on the line 44 of Figure 2;

Figure 5 is a fragmentary section on the line 5--5 of Figure 3;

Figure 6 is an exploded perspective view of a guide to be mounted on the table; and

Figure 7 is a plan view of the assembled guide on the table.

The apparatus illustrated on the drawing is designed for use in the home or a small shop, but the novel features are applicable to other and larger machines. As shown, the invention may be embodied in a table having a top 10 supported by a front wall 12, a rear wall 14, and side walls 16 and 18. The four walls and top of the table enclose a chamber in which is housed most of the operating apparatus.

A motor 20 drives a circular saw 22 and a planing knife 24 by means of belts 26, 28 and 30. The saw 22 and planing knife 24 are rotatably mounted respectively on the arms 32 and 34 of a rockable frame in the form of a bell-crank which includes a hub member 35 fixed on a transverse shaft 36 journalled in the side Walls 16 and 18 as indicated in Figure l. A short arm 38, integral with the bell crank, extends radially from the axis of the shaft 36. The end of the arm 38 is forked, the fork receiving a nut 40 which is pivotally attached thereto. A screw shaft 42 is journalled in the front wall 12 and is in threaded engagement with the nut 40. A suitable hand wheel or crank 44 is mounted on the end portion of the shaft 42 which projects outside of the wall 12. By manipulating the hand crank 44, the bell crank which carries the saw 22 and planing knife 24 can be rocked about the axis of the shaft 36 to cause a segment of the saw or a segment of the knife to project above the table top 10 any desired distance up to a maximum, as shown in Figure 2, so as to be in an operative position. By such adjustment, the saw can be made to cut kerfs of any desired depths in the under face of a work piece. Figure 3 shows the planing knife 24 in operative position. To accommodate these tools the table top is provided with a narrow opening or slot 46 for the saw, and a rectangular opening 48 for the planing knife.

In order to provide a unit that is comparatively small and light in weight but is rugged and strong in structure, each of the bell-crank arms 32 and 34 consists of a pair of parallel arms (Figures 4 and 5) projecting radially from the hub member 35 with bearings in their ends for tool shafts as hereinafter described.

Driving connections for the tools comprise the belt 26 which extends from a pulley 50 on the motor shaft to a pulley 52 (Figure 4) carried by the shaft 36 but rotatable freely thereon. The pulley 52 is a double one so that the belt 28 extends from it to a pulley 54 mounted on a tool shaft 56 journalled in hearings in the ends of the arms 34. On the tool shaft 56 also the planing knife 24 is mounted. A second pulley 58 is mounted on the shaft 56. The belt 30 extends from this pulley to a pulley 60 mounted on a tool shaft 62 journalled in bearings in the ends of the arms 32. On the tool shaft 62 also is mounted the saw 22. When the motor 20 is running, the saw 22 and knife 24 are continuously rotated regardless of their positions. By turning the hand crank 44 one way or the other either tool can be moved up into its operative position without interrupting the drive. This makes possible a quick and easy transition from either tool to the other without the necessity for reconnections or adjustment.

A slidable work guide is provided on the table top 10. The guide comprises a base consisting of a plate having on its bottom two parallel runners 72 which fit slidably in two channels 74 in the table top. These channels extend from front to rear and are parallel to the slot 46. The base 70 has a central, threaded hole 76 and a second threaded hole 78 offset from the hole 76. The rear corners of the base plate 70 are rounded off on arcs concentric with hole 76, as at 80. The base 70 supports an upper plate 82 which has a hole 84 through which projects the shank 86 of a screw 88 for threaded engagement in either the hole 76 or the hole 78. Integral with the upper plate 82 and at right angles thereto is a guide plate 90. This guide plate extends up above the level of the upper plate 82 and also down below it nearly to the surface of the table top 10. When the base plate is in place with its runners in the channels 74, the guide plate can be swung around the rounded corners to face in any direction from the rear (as in Figure 1) to either side (as in Figure 7). To adjust the angular position of the upper plate 82 and guide plate 90, the screw 88 is loosened, a knurled head 92 being provided for that purpose, the screw being tightened again after the plates 82 and 96 have been adjusted to the desired angular position. By shifting the screw 88 from the hole 76 to the hole 78, the guide can be set over nearer to the plane of the saw 22.

lclaim:

A multiple rotatable tool unit comprising a worktable having a top, front and rear walls, and side walls enclosing a chamber, a rock shaft journalled in said side Walls and extending from one side wall to the other, a hub member fixed on said shaft, a pair of parallel arms projecting radially from said hub member, bearings carried by the outer ends of said arms, a tool shaft journalled in said bearings, a rotary tool mounted on said tool shaft, a second pair of parallel arms projecting radially from said hub member and angularly spaced from the first said pair of arms, hearings in the outer ends of said second pair of arms, a second tool shaft journalled therein, a second rotatable tool mounted on said tool shaft, a motor mounted within said chamber, power transmission means operatively connecting said motor 7 3' and ,the two said toolshafts, said transmission means inciuding a pulley rotatably carried by said rock shaft and drivable by said motor, twopulleys mounted on the first said tool shaft; a sin'gle'pulley' mounted on said second tool shaft, ra helt connecting the-pulley on rockshaft with orieof saidttwo pulleys, a belgconnecting-the other of said two pulleysyvith said sing'le pulley, and means:

- for adjustably rocking said rock shaft,rsaid last named mounted on one of said walls in Which said adjusting- 4. shaft is rotatable but held against axial movement, and an operating handle on an end of said adjusting shaft.

References Cited in' the file of this patent UNITED STATES PATENTS 176,531 Hoffman V Apr. 25, 1876 1,139,659 FOX et a1." May 18, 1915 1,993,219 Merrigan Mar; 5, 1 935 2,058,681)" Gorsline 6t a1. Oetl' 27', 1936 2,530,296 Collins a Nov. 14, 1950 V a FOREIGN PAT NTS t 

